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This article investigates the problem of fixed‐time sliding mode consensus tracking for nonlinear second‐order multi‐agent system, in the presence of disturbances and actuator attacks. The interaction topology graph of multi‐agent system is directed and switched, and the switching topologies satisfy a more general persistent dwell‐time switching mechanism. To account for the disturbances, actuator attack, and switching topologies, a nonsingular sliding mode control law with distributed switching scheme is constructed to guarantee the fixed‐time reachability to a sliding surface. By using multiple Lyapunov functions, some new sufficient criteria are derived for fixed‐time consensus tracking of the multi‐agent system with persistent dwell‐time switching topologies. To illustrate the proposed approach, we present a numerical example and a physical example of the single pendulum model. [ABSTRACT FROM AUTHOR]

Purpose: To estimate the incidences of left renal vein (LRV) entrapment by right renal artery (RRA), a phenomenon primarily reported as case reports. Methods: The cross-sectional study consecutively screened renal vessel CT data of 38 (Renal) patients with nephropathy and 305 (Non-renal) patients with peripheral arterial diseases in a teaching hospital in northeast China between November 2018 and March 2023. The LRV compression by adjacent anatomical structures, including but not limited to RRA and multiple compression-related parameters, were investigated through multiplanar analysis of the CT data. Results: The overall LRV entrapment rates by adjacent structures were 41.93% (12/31) and 24.00% (6/25), the rates of RRA-sourced LRV compression 22.58% (7/31) and 20.00% (5/25), and the rates of compression by superior mesenteric artery (SMA) 16.13% (5/31) and 4.00% (1/25) in the Renal and Non-renal groups, respectively, with no significance. The venous segments distal to the RRA-compressed site had a significantly larger transectional lumen area than those of the non-compressed veins in both groups (3.09 ± 1.29 vs. 1.82 ± 0.23, p < 0.001 and 4.30 ± 2.65 vs. 2.12 ± 0.55, p = 0.006; maximum-to-minimum area ratios in Renal and Non-renal groups, respectively). Nearly 80% of RRAs were found arising anteriorly rightwards instead of passing straight to the right. Conclusion: RRA-sourced LRV compression was not rare, and its incidence was higher than that of the compression by SMA in both patient cohorts. RRA could be a more common compression source than SMA concerning LRV entrapment. Further investigations involving different populations, including healthy individuals, are needed. [ABSTRACT FROM AUTHOR]

Damascus rose (DR) is an important economic crop. In recent years, DR has been widely planted and utilized in China. In order to improve its aroma quality, the volatile releasing regularities of DR need to be studied. Therefore, HS‐GC‐IMS were used to examine the style of aroma release in DR under three flowering states: pre‐bloom (PB), half‐bloom (HB) and full bloom (FB). The results show that HS‐GC‐IMS detected 56 volatile compounds to investigate the changes of volatile compounds in three states of DR during the growth period. The results of PCA showed that changes in aroma substances were obvious during the growth stage of DR. In addition, FB contributed some key aroma molecules of DR. Thus, volatiles in DR at different times of a day (5 AM, 11 AM, 5 PM) and were further examined by using P&T‐GC–MS towards FB. Finally, a total of 68 volatile compounds were identified; most of them were terpenoids (47.83%–59.62%). Totally 21 volatiles were considered key compounds due to their high concentration (≥1%). These key compounds showed the highest levels at 5 AM and lowest levels at 5 PM. Heat map clustering showed that most of the key compounds possessing higher levels in the flowers had maximum levels at 5 AM and compounds with lower levels peaked at 11 AM. This study will provide a theoretical understanding of the aroma generation mechanism of DR. It also helps the rose farmers to plant and sow rose flowers practically. [ABSTRACT FROM AUTHOR]

Pixel-level classification of very-high-resolution images is a crucial yet challenging task in remote sensing. While transformers have demonstrated effectiveness in capturing dependencies, their tendency to partition images into patches may restrict their applicability to highly detailed remote sensing images. To extract latent contextual semantic information from high-resolution remote sensing images, we proposed a gaze–saccade transformer (GSV-Trans) with visual perceptual attention. GSV-Trans incorporates a visual perceptual attention (VPA) mechanism that dynamically allocates computational resources based on the semantic complexity of the image. The VPA mechanism includes both gaze attention and eye movement attention, enabling the model to focus on the most critical parts of the image and acquire competitive semantic information. Additionally, to capture contextual semantic information across different levels in the image, we designed an inter-layer short-term visual memory module with bidirectional affinity propagation to guide attention allocation. Furthermore, we introduced a dual-branch pseudo-label module (DBPL) that imposes pixel-level and category-level semantic constraints on both gaze and saccade branches. DBPL encourages the model to extract domain-invariant features and align semantic information across different domains in the feature space. Extensive experiments on multiple pixel-level classification benchmarks confirm the effectiveness and superiority of our method over the state of the art. [ABSTRACT FROM AUTHOR]

Invasive fungal infections (IFIs) are common and life-threatening complications in post-hematopoietic stem cell transplantation (post-HSCT) recipients, Severe IFIs can lead to systemic infection and organ damage, which results in high mortality in HSCT recipients. With the development of the field of fungal infection diagnosis, more and more advanced non-culture diagnostic tools have been developed, such as glip biosensors, metagenomic next-generation sequencing, Magnetic Nanoparticles and Identified Using SERS via AgNPs+ , and artificial intelligence-assisted diagnosis. The advanced diagnostic approaches contribute to the success of HSCT and improve the overall survival of post-HSCT leukemia patients by supporting therapeutical decisions. This review provides an overview of the characteristics of two high-incidence IFIs in post-HSCT recipients and discusses some of the recently developed IFI detection technologies. Additionally, it explores the potential application of cationic conjugated polymer fluorescence resonance energy transfer (CCP-FRET) technology for IFI detection. The aim is to offer insights into selecting appropriate IFI detection methods and gaining an understanding of novel fungal diagnostic approaches in laboratory settings. [ABSTRACT FROM AUTHOR]

The purpose of this research is to investigate the influence of SO42− in aerobic/anaerobic environment and its interaction with HCO3− on the corrosion behavior of Q345 carbon steel using potentiodynamic polarization, X-ray diffraction, white-light interferometer, electrochemical impedance spectroscopy and scanning electron microscopy methods. It was found that the corrosion rates of Q345 carbon steel are faster in aerobic environment under the synergistic effects of SO42− and dissolved oxygen compared to that in the absence of oxygen. In solutions containing SO42− and HCO3− in anaerobic environment, a high proportion of HCO3−/SO42− leads to the passivation of Q345 carbon steel sample as a result of the competitive adsorption of HCO3− on substrate surface with smaller radius. As the ratio of HCO3−/SO42− decreases, the presence of SO42− can enhance the dissolution of Fe matrix, thereby resulting in the corrosion of specimens. High concentration of HCO3− also exhibits the suppression on corrosion because of the formation of dense corrosion products. [ABSTRACT FROM AUTHOR]

In industrial manufacturing, how to accurately classify defective products and locate the location of defects has always been a concern. Previous studies mainly measured similarity based on extracting single‐scale features of samples. However, only using the features of a single scale is hard to represent different sizes and types of anomalies. Therefore, the authors propose a set of memory banks of multi‐scale features (MBMF) to enrich feature representation and detect and locate various anomalies. To extract features of different scales, different aggregation functions are designed to produce the feature maps at different granularity. Based on the multi‐scale features of normal samples, the MBMF are constructed. Meanwhile, to better adapt to the feature distribution of the training samples, the authors proposed a new iterative updating method for the memory banks. Testing on the widely used and challenging dataset of MVTec AD, the proposed MBMF achieves competitive image‐level anomaly detection performance (Image‐level Area Under the Receiver Operator Curve (AUROC)) and pixel‐level anomaly segmentation performance (Pixel‐level AUROC). To further evaluate the generalisation of the proposed method, we also implement anomaly detection on the BeanTech AD dataset, a commonly used dataset in the field of anomaly detection, and the Fashion‐MNIST dataset, a widely used dataset in the field of image classification. The experimental results also verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Key message: GhAP genes were identified as the candidates involved in cotton fiber length under the scope of fine mapping a stable fiber length QTL, qFLD05. Moreover, the transcription factor GhWRKY40 positively regulated GhAP3 to decrease fiber length. Fiber length (FL) is an economically important fiber quality trait. Although several genes controlling cotton fiber development have been identified, our understanding of this process remains limited. In this study, an FL QTL (qFLD05) was fine-mapped to a 216.9-kb interval using a secondary F2:3 population derived from the upland hybrid cultivar Ji1518. This mapped genomic segment included 15 coding genes, four of which were annotated as aspartyl proteases (GhAP1-GhAP4). GhAPs were identified as candidates for qFLD05 as the sequence variations in GhAPs were associated with FL deviations in the mapping population, and functional validation of GhAP3 and GhAP4 indicated a longer FL following decreases in their expression levels through virus-induced gene silencing (VIGS). Subsequently, the potential involvement of GhWRKY40 in the regulatory network was revealed: GhWRKY40 positively regulated GhAP3’s expression according to transcriptional profiling, VIGS, yeast one-hybrid assays and dual-luciferase experiments. Furthermore, alterations in the expression of the eight previously reported cotton FL-responsive genes from the above three VIGS lines (GhAP3, GhAP4 and GhWRKY40) implied that MYB5_A12 was involved in the GhWRKY40-GhAP network. In short, we unveiled the unprecedented FL regulation roles of GhAPs in cotton, which was possibly further regulated by GhWRKY40. These findings will reveal the genetic basis of FL development associated with qFLD05 and be beneficial for the marker-assisted selection of long-staple cotton. [ABSTRACT FROM AUTHOR]

Fibrodysplasia ossificans progressiva (FOP; MIM# 135100) is an ultra-rare congenital disorder caused by gain-of-function point mutations in the Activin receptor A type I (ACVR1, also known as ALK2) gene. FOP is characterized by episodic heterotopic ossification (HO) in skeletal muscles, tendons, ligaments, or other soft tissues that progressively causes irreversible loss of mobility. FOP mutations cause mild ligand-independent constitutive activation as well as ligand-dependent bone morphogenetic protein (BMP) pathway hypersensitivity of mutant ACVR1. BMP signaling is also a key pathway for mediating acquired HO. However, HO is a highly complex biological process involving multiple interacting signaling pathways. Among them, the hypoxia-inducible factor (HIF) and mechanistic target of rapamycin (mTOR) pathways are intimately involved in both genetic and acquired HO formation. HIF-1α inhibition or mTOR inhibition reduces HO formation in mouse models of FOP or acquired HO in part by de-amplifying the BMP pathway signaling. Here, we review the recent progress on the mechanisms of the HIF-1α and mTOR pathways in the amplification of HO lesions and discuss the future directions and strategies to translate the targeting of HIF-1α and the mTOR pathways into clinical interventions for FOP and other forms of HO. [ABSTRACT FROM AUTHOR]

This meta-analysis aims to systematically compare the efficacy between phacoemulsification (PE) combined with goniosynechialysis (GSL) and PE alone for primary angle-closure disease (PACD) patients. All the data were searched from the PubMed, EMBASE and the Cochrane Library. The Cochrane Handbook was used to evaluate the quality of the included studies. Additionally, this meta-analysis was performed by using the Revman 5.4 software. Nine randomized controlled trials (RCTs) were included in this study. Compared with PE alone group, PE+GSL could result significant reduction in the IOP (MD, 1.81; p = 0.002). In the instrumental subgroup, also more reduction of IOP was shown in the PE+GSL group (MD, 2.11; p = 0.02). In the viscogonioplasty (VGP) subgroup, there was not no statistical difference between PE alone group and PE+GSL group (MD, 1.53; p = 0.11). Also, more reduction of peripheral anterior synechiae (PAS) was shown in the PE+GSL group (MD,59.15; p<0.00001). For the change in angle open distance (AOD)500, AOD 750, trabecular-iris space (TISA)500, number of glaucoma medications and best corrected visual acuity (BCVA), there was no difference between two groups (p = 0.25, 0.35, 0.17, 0.56, 0.08). For TISA 750, more improvement was shown in the PE+GSL group (p<0.00001). Instrumental separation had better effect on lowering IOP when it combined with PE. Both instrumental separation and VGP could reduce postoperative PAS. The operation of GSL has no obvious effect on postoperative vision. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare the therapeutic effects of activated platelet-rich plasma (PRP) prepared from elderly individuals and young adults to treat pressure ulcers (PUs), and to accumulate a theoretical basis for allogeneic PRP treatment of PUs in elderly patients. Whole blood was extracted from elderly individuals aged >65 y and young adult volunteers for PRP preparation, and platelet concentrations in whole blood and PRP were compared. Growth factors released from activated PRP were assayed using the enzyme-linked immunosorbent assay. C57BL/6 mice were divided into three groups: the control saline, elderly-PRP (Group A), and young adult-PRP (Group B). Ischemia-reperfusion injury-induced PUs were established on the backs of mice. PUs were photographed on days 0, 5, and 10 to assess their sizes. Specimens were collected on day 10 and subjected to hematoxylin and eosin and Masson's staining. Immunohistochemical staining for CD31 was conducted to evaluate vascular formation, and cell invasion was assessed using a Transwell assay. The action of PRP on transforming growth factor-beta (TGF-β)-dependent fibroblast activity and epithelial-mesenchymal transition was analyzed using immunofluorescence and Western blotting in vitro. The platelet concentrations in whole blood and PRP of young adults were significantly higher than that in elderly individuals. The two PRP treatment groups had similar platelet enrichment coefficients of PRP. After activation, PRP from young adults produced significantly higher levels of platelet-derived growth factor, TGF-β, and vascular endothelial growth factor than PRP from elderly individuals (P < 0.05). The concentrations of platelet-derived growth factor, TGF-β, and vascular endothelial growth factor were positively correlated with the platelet concentrations in whole blood and PRP. The effects of PRP in regulating the expressions of TGF-β, α-smooth muscle actin, vimentin, and E-cadherin were observed in vivo and in vitro. The two PRP treatment groups exhibited better wound healing than the control group, as evidenced by more re-epithelialization, higher collagen content, skin fibrosis, and more blood vessel formation over time. Group B exhibited better wound healing than Group A (P < 0.05). PRP exhibits potent wound healing ability in PU therapy, and PRP from young adults is seemingly superior to that from elderly individuals because of a higher concentration of platelets and increased production of growth factors. [ABSTRACT FROM AUTHOR]

Koi is a brightly coloured, elegant fish with high ornamental value, and is known as a "swimming work of art". Fish body colour is mainly determined by the type and distribution of pigment cells on the skin or scales. In this paper, the composition, distribution and morphology of pigment cells in the scales and skin of four different body colours, namely, black, white, yellow and red koi, were compared. The composition of pigment cells in the scales and skin was consistent, and rich iridescent cells were present in all four koi, with melanophores in black koi, and xanthophores and erythrophores in yellow and red koi. Only iridophores were observed in white koi. The ultrastructure of iridophores in all four koi colours was observed by transmission microscopy, and the iridophores mainly had three different morphologies: pike-shaped, short rod-shaped and vacuolated. Real-time fluorescence quantitative PCR was used to detect the expression of eight iridocyte development-related genes in the skin of four different body colors of koi carp, the results showed that eight genes related to iridophores development were expressed in the skin of different body colours, whereas there were differences in expression, among which the relative expression of alk, pka, sox10, pax3, foxd3 and pnp4a genes was higher in red and yellow koi, while the relative expression of ltk and alx4a genes was the highest in white koi. In order to further confirm the role of the pnp4a genes in iridophores development, the recombinant plasmid of overexpression of pnp4a gene was constructed, and was microinjected into the fertilized eggs of AB zebrafish. In order to further confirm the role of pnp4a gene in fish body colour formation, especially in iridophores, we constructed a pnp4a overexpression recombinant plasmid and microinjected it into the fertilized eggs of zebrafish (AB). [ABSTRACT FROM AUTHOR]

The conventional two-beam interferometry adopts only one expression about plasma density and thickness because only fringe shift is recognized from the recorded fringes. Therefore, the prior hypotheses that the plasma is thickness-uniform or circular symmetry have to be introduced to separate them, which limits the applied range and accuracy of the conventional method. This paper found that the laser beam will be deflected if the thickness changes, leading the recorded fringes to be defocused. As a result, a new expression relying on recognizing the defocus parameter of the recorded fringes is derived, and a pointwise separation algorithm to separate density and thickness is proposed based on the two expressions. Compared to the conventional algorithms, the new algorithm requires no hypotheses and thus has a wider applied range. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are non-coding RNAs, which, as members of the RNA interference pathway, play a pivotal role in antiviral infection. Almost 80% of plant viruses are transmitted by insect vectors; however, little is known about the interaction of the miRNAs of insect vectors with plant viruses. Here, we took rice black-streaked dwarf virus (RBSDV), a devastating virus to rice production in eastern Asia, and the small brown planthopper, (SBPH, Laodelphax striatellus) as a model to investigate the role of microRNA750-3p (miR750-3p) in regulating viral transmission. Our results showed that Ls-miR750-3p was downregulated in RBSDV-infected SBPH and predominately expressed in the midgut of SBPH. Injection with miR750-3p agomir significantly reduced viral accumulation, and the injection with the miR750-3p inhibitor, antagomir-750-3p, dramatically promoted the viral accumulation in SBPH, as detected using RT-qPCR and Western blotting. The processing of precursor 7 (POP7), a subunit of RNase P and RNase MRP, was screened, identified, and verified using a dual luciferase reporter assay as one target of miR750-3p. Knockdown of POP7 notably increased RBSDV viral propagation in SBPH and then increased the viral transmission rate by SBPH. Taken together, our data indicate that miR750-3p targets POP7 to suppress RBSDV infection in its insect vector. These results enriched the role of POP7 in modulating virus infection in host insects and shared new insight into the function of miRNAs in plant virus and insect vector interaction. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we ask whether the invasive Datura stramonium bring about effects on native plants in three different habitats, including farmland, wasteland and roadside. Studying the invaded and uninvaded areas in these habitats, we found that the invasion of D. stramonium brought about corresponding effects on the functional traits of native plants and the stoichiometric characteristics of soil carbon, nitrogen and phosphorus. These findings imply that invasion by D. stramonium has a great effect on the local ecosystem, and it has a high ability to capture resources. D. stramonium can improve its own competitiveness by enhancing invasiveness by changing the functional traits of native plants and the stoichiometric characteristics of soil C, N and P, which may be the reason for its invasive success. Datura stramonium is an invasive herb of the family Solanaceae from Mexico and has been invading seriously in China. The effects of invasive plants on the functional traits of native plants and the stoichiometric characteristics of soil carbon, nitrogen and phosphorus in different habitats were explored by taking the invasive plant D. stramonium and coexisting native plants as the research object. The species, quantity and height of plants in sample plots in farmland, wasteland and roadside habitats were investigated and the specific leaf area (SLA), leaf carbon content (C), nitrogen content (N), carbon-to-nitrogen ratio (C:N), construction cost (CCmass) and stoichiometric characteristics of soil carbon (C), nitrogen (N) and phosphorus (P) were analyzed. The results showed that compared with the noninvaded area, the species and quantity of native plants decreased in the invaded area, and SLA and leaf N showed a decreasing trend. The plant height of native plants in the invaded area of the farmland and wasteland decreased by 23.19% and 15.26%, respectively, while the height of native plants along the roadside increased by 95.91%. The leaf C:N ratio of native plants in the invaded area along the roadside significantly increased by 54.07%. The plant height and leaf N of D. stramonium in the three habitats were higher than those of the native plants. The soil N in the invaded area of the three habitats increased, with the soil N in the farmland increasing by 21.05%, in the wasteland increasing by 9.82% and along the roadside significantly increasing by 46.85%. The soil carbon-to-phosphorus ratio (C:P) in the three habitats showed an increasing trend. The soil C:P ratio in the farmland increased by 62.45%, in the wasteland it increased by 11.91% and along the roadside it significantly increased by 71.14%. These results showed that invasion by D. stramonium has a great effect on the local ecosystem, and it has a high ability to capture resources. D. stramonium can improve its own competitiveness by enhancing invasiveness by changing the functional traits of native plants and the stoichiometric characteristics of soil C, N and P, which may be the reason for its invasive success. [ABSTRACT FROM AUTHOR]

Studies about the role of urban characteristics in modifying the health effect of temperature extremes are still unclear. This study is aimed at quantifying the morbidity risk of infectious diarrhea attributable to temperature extremes and the modified effect of a range of city-specific indicators. Distributed lag non-linear model and multivariate meta-regression were applied to estimate fractions of infectious diarrhea morbidity attributable to temperature extremes and to explore the effect modification of city-level characteristics. Extreme heat- and extreme cold-related infectious diarrhea amounted to 0.99% (95% CI: 0.57–1.29) and 1.05% (95% CI: 0.64–1.24) of the total cases, respectively. The attributable fraction of temperature extremes on infectious diarrhea varied between southern and northern China. Several city characteristics modified the association of extreme cold with infectious diarrhea, with a higher morbidity impact related to increased water consumption per capita and decreased latitude. Regions with higher levels of latitude or GDP per capita appeared to be more sensitive to extreme hot. In conclusion, exposure to temperature extremes was associated with increased risks of infectious diarrhea and the effect can be modified by urban characteristics. This finding can inform public health interventions to decrease the adverse effects of temperature extremes on infectious diarrhea. [ABSTRACT FROM AUTHOR]

Adhesion is easily affected by moisture erosion, thus reducing pavement performance. SBS modified asphalt is widely used in road engineering due to its excellent performance. For analyzing the adhesion properties between SBS modified asphalt and aggregates under moisture damage, the macro-scale SBS modified asphalt-coated aggregates and micro-scale asphalt-aggregate adhesion models were prepared first. The moisture damage was applied to the coated aggregates and adhesion models subsequently. After that, the quantitative boiling tests and molecular dynamics (MD) simulations were carried out. Finally, the multi-scale adhesion results were analyzed using Pearson correlation analysis. The macro-scale results imply that as the degree of moisture damage increases, the stripping area of the asphalt-aggregate interface rises. The micro-scale results reveal the moisture damage mechanism that is the penetrated moisture into asphalt-aggregate interface disrupt the adhesion force by the action of hydrogen bonds and Van der Waals forces. The Pearson correlation coefficient is 0.996, which indicates that the multi-scale adhesion results present an extremely strong linear relationship. This research contributes to the analysis of moisture damage in asphalt pavements in pluvial as well as seasonal frozen regions, and also provides a reference for correlation analysis between the multi-scale results. [ABSTRACT FROM AUTHOR]

Using supercritical CO2 as a heat transfer fluid in microchannel receivers is a promising alternative for tower concentrating solar power plants. In this paper, the heat transfer and flow characteristics of supercritical CO2 in microchannels at high temperature are investigated by numerical simulations. The effects of microchannel structure, mass flow rate, heat flux, pressure, inlet temperature and radiation are analyzed and discussed. The results show that higher mass flow rate obtains poorer heat transfer performance with larger flow resistance of supercritical CO2 in microchannels at high temperature. The fluid and wall temperatures, average heat transfer coefficient and pressure drop all increase nearly linearly with the increases in heat flux and inlet temperature in the high-temperature region. Moreover, high pressure contributes to great hydraulic performance with approximate thermal performance. The effect of radiation on thermal performance is more pronounced than that on hydraulic performance. Furthermore, the optimized structures of inlet and outlet headers, as well as those of the multichannel in the microchannels, are proposed to obtain good temperature uniformity in the microchannels with relatively low pressure drop. The results given in the current study can be conducive to the design and application of microchannel receivers with supercritical CO2 as a heat transfer fluid in the third generation of concentrating solar power plants. [ABSTRACT FROM AUTHOR]

Given in the plane a set S of m point sites in a simple polygon P of n vertices, we consider the problem of computing the geodesic farthest-point Voronoi diagram for S in P. It is known that the problem has an Ω (n + m log m) time lower bound. Previously, a randomized algorithm was proposed [Barba, SoCG 2019] that solves the problem in O (n + m log m) expected time. The previous best deterministic algorithms solve the problem in O (n log log n + m log m) time [Oh, Barba, and Ahn, SoCG 2016] or in O (n + m log m + m log 2 n) time [Oh and Ahn, SoCG 2017]. In this paper, we present a deterministic algorithm that takes O (n + m log m) time, which is optimal. This answers affirmatively an open question posed by Mitchell in the Handbook of Computational Geometry two decades ago. [ABSTRACT FROM AUTHOR]

A nanofluidic system consists of a nano-porous medium and functional liquid, which demonstrates a higher energy absorption density compared to conventional systems for energy absorption. Alterations in the composition of the functional liquid can significantly impact the properties of a nanofluidic system. In this paper, the widely used zeolite ZSM-5 was chosen as the porous medium to establish a nanofluidic system. Three distinct electrolyte solutions, namely KCl aqueous solutions, NaCl aqueous solutions and MgCl2 aqueous solutions were employed as functional liquids while pure water served as the reference condition for configuring four kinds of nanofluidic systems. Pressure-induced percolation experiments were performed on the four zeolite-based systems. The difference in the infiltration process between the electrolyte solution systems and the deionized water system has been ascertained. The effect of the ion size on the infiltration and defiltration process has been determined. The results show that the introduction of ions induces a hydration effect, resulting in a higher critical infiltration pressure of the electrolyte solution system compared to an aqueous solution system. The magnitude of cation charge directly correlates with the strength of the hydration effect and the corresponding increase in critical infiltration pressure. Upon entering the nanochannel, the liquid infiltrates primarily in the form of ions rather than a cation hydration form. The larger the ion size, the shallower the penetration depth after entering the nanopore channel and the larger the corresponding relative outflow rate. The present work will provide valuable theoretical complementary and experimental data support for nanofluidic system applications. [ABSTRACT FROM AUTHOR]

To investigate the stability and electrical and physical properties of undoped CuO and CuO doped with rare earth elements, electronic structures and elastic constants were calculated using first-principles density functional theory. Additionally, experimental verification was carried out on AgCuO and AgCuO-X (La, Ce, Y) electrical contacts, which were prepared using sol–gel and powder metallurgy methods. The contacts were tested under an 18 V/15 A DC resistive load using the JF04D contact material testing system. Arc parameters were analyzed, and three-dimensional surface profilometry and scanning electron microscopy were used to study the altered erosion morphology of the electrically contacted materials; moreover, the potential mechanisms behind their arc erosion behavior were investigated in depth. The results demonstrate that the doping of rare earth elements can improve the electrical conductivity and physical properties of the contacts, optimize the arc parameters, and enhance their resistance to arc erosion. Notably, AgCuO-Ce exhibited the highest electrical conductivity and the least amount of material transfer; moreover, it had excellent arc time and energy parameters, resulting in the best resistance to arc erosion. This study provides a theoretical basis for the screening of doping elements to enhance the performance of AgCuO contact materials and offers new ideas and scientific references for this field. [ABSTRACT FROM AUTHOR]

Most of the depth restoration algorithms are complicated for a single defocused image, the restoration effect is poor on the image edges, complex textures and shadow areas. In this paper, the depth of a scene is recovered by a single image defocus cue, a novel approach of single defocused image depth restoration is proposed based on superpixel segmentation. First, the simple linear iterative cluster (SLIC) is used to divide the original image into several superpixel modules. Then, the defocus blur amount of each superpixel module is obtained according to the Gaussian–Cauchy mixed model, so as to obtain the superpixel-level sparse depth map. Finally, the cellular automata model is used to optimize the obtained sparse depth map and to restore the true and accurate panoramic depth map. Compared with other methods, the algorithm not only minimizes the error, but also simplifies the process of extending the edge defocus blur to the global. The experimental results on real data show that the method is not only less time-consuming, but also can effectively improve the depth recovery effect in areas with unclear edges, complex textures and shadows. These demonstrate the effectiveness of the method in providing reliable estimates of scene depth. [ABSTRACT FROM AUTHOR]

The effects of metal doping on the structural and physical properties of AgSnO 2 contactors were investigated using simulations and experiments based on first-principles calculations. The electrical contact test system was tested for 20,000 electrical contacts to check the physical properties under 24 V/15 A DC resistive load and analyze the relationship between the parameters. The erosion morphology of the contact material was characterized by a 3D surface profilometer, and the mechanism of the molten pool force, material transfer, and arc erosion behavior was studied in detail. The results show that metal doping can improve the thermal stability, mechanical properties and electrical conductivity of the materials, and significantly affect the crystalline and electronic structure of the materials, resulting in better stability and resistance to arc erosion. The best arc erosion performance of AgSnO 2 –Y is related to its superior thermal stability and electrical properties, while the better arc erosion performance of AgSnO 2 –Cu is probably related to its good mechanical properties. In addition, metal doping has a significant effect on the arc formation and interruption of AgSnO 2 contactors and leads to a change in the material transfer mode. This study provides a feasible method for the analysis of metal doping to improve the erosion performance of contact materials and provides a valuable reference for the further development of research on arc erosion resistance of contactors. [ABSTRACT FROM AUTHOR]

Novel peroxide-initiating monomer with the peroxide group and the polymerizable vinyl double bond was designed and prepared through cheap industrial chemical reactants and facile synthesis. Here, one kind of the peroxide-initiating monomer 2-(tert-butylperoxy)ethyl methacrylate (BPEMA) prepared through three-step simple chemical reactions, using tert-butyl hydroperoxide and 2-bromoethanol as the raw ingredients, which reacted at low temperature and obtained the 2-tert-butyl peroxy ethanol, then esterified with methacryloyl chloride or isobutyryl chloride to obtain the peroxide-initiating monomer 2-(tert-butylperoxy)ethyl methacrylate(BPEMA). The analogue peroxide-initiating compound 2-(tert-butylperoxy)ethyl isobutyrate (BPEIB) was designed and obtained using the same reactions as those employed with BPEMA. The other kind of the peroxide-initiating monomer 2-hydroperoxide ethyl methacrylate (HPEMA). The purity of the three products was determined to be above 95%. Here, develop convenient and effective methods in using peroxide-initiating monomer for the in-depth study on the preparation of branched polymers. [ABSTRACT FROM AUTHOR]

Polyphosphoric acid (PPA) and styrene–butadiene–styrene (SBS) were adopted to produce PPA-SBS-modified bio-blend bitumen, which achieved excellent mechanical performance. However, its long-range performance, such as the fatigue and thermal cracking behavior under long-term thermal oxidation, is not well understood. Therefore, a pressure aging vessel (PAV) system was applied to simulate the aging behavior of the bitumen under the action of thermal oxidation. Then, a linear amplitude sweep (LAS) test combined with a viscoelastic continuum damage (VECD) model was applied to investigate the fatigue properties of the bitumen. Moreover, a bending beam rheometer (BBR) test was conducted to evaluate the thermal cracking resistance of the bitumen before and after PAV aging. Meanwhile, an atomic force microscope (AFM) was applied to observe the microscopic topography. The results show that the original compound-modified bitumen can bear more fatigue damage than that of the control bitumen at the failure point, and it also has excellent fatigue resistance at 2.5%, 5%, 7.5%, and 10% applied strain. Moreover, the VECD model can accurately predict the fatigue life of the bitumen under different applied strains. The variation ratio of stiffness modulus for the compound-modified bitumen is below that of the control bitumen after PAV aging, so it shows a better anti-aging performance. Finally, the AFM test shows that PPA and bio-bitumen decrease the heterogeneity of the bitumen, reducing the difference between phases. [ABSTRACT FROM AUTHOR]

A mathematical model is proposed to simulate the fully hydro-mechanical coupling of two-phase cement-based slurry migration in saturated deformable geomaterials from microscopic to macroscopic scale. The mass conservation equations and the momentum balance equations for cement-based slurry and geomaterials are derived based on the thermodynamically constrained averaging theory (TCAT). The Galerkin discretization of the governing equations of hydro-mechanical coupling are developed by the isogeometric analysis (IGA) integrated with the Bézier extraction operator, and the numerical calculation is implemented with the generalized backward Euler method. The presented modeling is verified by comparison of the numerical calculation with the experimental tests, and the pore fluid pressure of the stratum and the slurry concentration of cement-based slurry migration in saturated deformable geomaterials are discussed. The modeling presented provides an effective alternative method to simulate cement-based slurry migration and explore isothermal multiphase coupled problems. [ABSTRACT FROM AUTHOR]

Video person re-identification(re-ID) plays an important role in intelligent video surveillance, which can automatically match the same person across video clips under non-overlapping cameras. Despite great progress in re-ID, the performance of most existing methods still is corrupted severely under partial occlusion. Although some multi-granularity methods have alleviated this dilemma, these methods still suffer from weak diversity of features and conflict between rigid horizontal partition and vertical occlusion. In this paper, we propose a novel video person re-ID framework, called Multi-Granularity Occlusion Aware (MGOA), which extracts multi-granularity features by precisely erasing the occlusion. Different from previous works based on multiple granularities, the proposed MGOA predicts the partial occlusion in a coarse-to-fine manner instead of erasing the occlusion in video clips by one step. Specifically, we first propose the multi-granularity feature extraction to obtain diverse features at different levels of feature maps, which is beneficial for the fine erasure of the occlusion. Moreover, to avoid the limitation of horizontal stripes that cannot handle vertical occlusion, we design Attention-Aware Occlusion Erasure (AA-OE) that can obtain the attention maps with coarse occlusion erasure in the coarse-grained branch and the attention maps with fine occlusion erasure in the fine-grained branch. It is worth noting that each granularity in our network is not independent but relevant through the top-down information transmission between granularities, which transfers the erased occlusion feature maps of the current branch to the next finer-grained branch for guiding AA-OE to obtain more discriminative features. Extensive experiments on three challenging public benchmarks show that our MGOA can deal well with occlusion and achieves state-of-the-art performance. [ABSTRACT FROM AUTHOR]

Asphalt pavements often experience damage from freeze–thaw cycles in seasonal frozen regions, and asphalt–aggregate adhesion is essential to asphalt mixtures' ability to withstand freeze–thaw damage. To quantitatively investigate the effect of asphalt–aggregate adhesion on mechanical performance of asphalt mixtures under freeze–thaw cycles, in this study, loose asphalt stones were prepared with coarse aggregates, and the quantitative boiling test was performed to evaluate the asphalt–aggregate adhesion property under freeze–thaw cycles at first; subsequently, the high-temperature creep and low-temperature splitting test were adopted with the stone matrix asphalt (SMA) to evaluate the mechanical performance under freeze–thaw cycles; finally, the gray relation analysis (GRA) method was used to analyze the relationship between the asphalt–aggregate adhesion property and mechanical performance. The results suggested that the asphalt–aggregate adhesion property decreased rapidly as the freeze–thaw cycle increased. The high-temperature viscous strain increased 346.13%, and the low-temperature strain energy decreased 14.34% after 21 freeze–thaw cycles. Through the GRA method, it was found that asphalt–aggregate adhesion properties with 4.75 and 9.5 mm sieve-size aggregates had a greater impact on the elastic and viscous properties of SMA, respectively. This study contributes to the design of SMA in seasonal frozen regions and provides a reference to study the damage mechanism of other types of asphalt mixtures in seasonal frozen regions. [ABSTRACT FROM AUTHOR]

The hydrogen-dependent and methylotrophic order Methanomassiliicoccales consists of the families Methanomethylophilaceae and Methanomassiliicoccaceae. While Methanomethylophilaceae are comparatively well studied, there is a lack of knowledge on Methanomassiliicoccaceae. In this 16S rRNA gene amplicon sequencing-based study we investigated the temporal and spatial dynamics of the Methanomassiliicoccales in drained and rewetted sites of three common temperate fen peatlands. A 2.5-year monitoring of the fen microbiome composition at three peat depths revealed a dynamic methanogen and Methanomassiliicoccales composition across space and time. Four Methanomassiliicoccales phylotypes were found and they were differentially distributed between the fen types. The wetland cluster phylotype was omnipresent and dominant in abundance in all sites along all depths. The Methanomassiliicoccus phylotype was highly abundant in topsoil while the AB364942 phylotype was exclusively found in deeper regions of the rewetted percolation fen. The phylotype affiliated with Methanomassiliicoccales strain U3.2.1 was only detected in the rewetted percolation fen. We discuss the distribution of the four phylotypes with implications for their ecophysiology, where oxygen tolerance and substrate spectrum might play major roles. In conclusion, the Methanomassiliicoccales are widespread and account for a significant proportion of methanogens, which might suggest their importance for methane emissions from peatlands. [ABSTRACT FROM AUTHOR]

In this article, we propose the endothermic screen model. The aim is to reduce the problems of the high temperature and low utilization of waste heat in industrial plants with high radiant heat. In this paper, the Rhino software is used to establish the model and import it into the FLUENT software, divide the mesh, set the boundary conditions and analyze the transient temperature field. Finally, the temperature change law in the plant and the waste heat recovery efficiency of the endothermic screen are obtained. The flow of cooling water in the endothermic screen is used to transform and transfer the high-radiation heat inside the plant to the outside. The simulation results show that after adding the endothermic screen, the average indoor temperature drops from 313.33 K to 305.66 K, which has a cooling effect. The waste heat recovery efficiency reaches up to 56%, and the waste heat recovery effect is obvious. The research results can provide a reference for the application of an endothermic screen in actual high radiant heat plants and provide a more comfortable working environment for the plant workers. [ABSTRACT FROM AUTHOR]

Exploratory behaviour is one of the best-investigated behavioural traits. However, little is known about the influence of personality on novel food preferences in the social context, i.e., whether knowledge and previous experience can influence individual preference or if the presence of conspecifics can alter their choice. In the present study, we examined in cinereous tit (Parus cinereus) whether individuals with different personality types in the social context will prefer their own previously chosen novel food or change their preference in the presence of conspecifics. Second, we studied how the presence and behaviour of conspecifics may mediate individual personality. We conducted a standardized personality assay (exploratory behaviour) to analyse the individual personality. Birds were trained and provided with three different types of novel human-derived materials in both asocial and social contexts (with a conspecific). We recorded the latency to feed, time spent at the feeder, and the number of visits by fast and slow explorers in the two contexts, i.e., asocial and social. After the analyses of experimental data, we found that fast-exploring cinereous tits preferred peanuts in an asocial context, while slow explorers consumed a greater amount of sunflower seeds. In the social context, individuals of both personality types preferred peanuts to sunflower seeds. Additionally, individuals took less latency to eat food, made more visits to the feeder, and spent more time at the feeder in the social context than in the asocial context. Our findings show that foraging success may be determined by personality and social context. However, personality traits may be subject to constraints arising from correlations with other behavioural traits, and it remains a major challenge to understand the functional significance of individual foraging strategies. [ABSTRACT FROM AUTHOR]

Thyroid autoimmunity is a potentially critical factor that is often neglected in the association between subclinical hypothyroidism (SCH) and depressive disorders. This study aimed to investigate the clinical correlates of autoimmune thyroiditis (AIT) and non-autoimmune hypothyroidism (NAIH) in treatment-naïve patients with major depressive disorder (MDD). Using a cross-sectional design, we recruited a total of 1718 outpatients with treatment-naïve MDD. Demographic and relevant clinical information including duration of MDD, severity of depression and anxiety, psychotic symptoms, suicide attempts, thyroid function parameters, etc. were collected. According to thyroid function parameters, patients were classified as AIT, NAIH, latent Hashimoto's thyroiditis (LH) and euthyroidism (ET). Patients with SCH (including AIT and NAIH) had older age at onset, and were more likely to have psychotic symptoms compared to those with ET. Multiple linear regression analysis showed that SCH was associated with duration of MDD and HAMD scores. Logistic regression analysis showed that the odds of having more severe anxiety and metabolic syndrome were greater among patients with SCH compared to those with ET. The odds of having suicide attempts were greater among patients with AIT than among those with ET. Because of the cross-sectional design of this study, we were unable to sort out causality between MDD and SCH. Our findings suggested that AIT and NAIH were associated with duration of MDD, HAMD scores, severity of anxiety, and metabolic syndrome. However, only AIT in SCH was associated with suicide attempts. • SCH (including AIT and NAIH) is associated with duration of MDD, HAMD scores, severity of anxiety, and metabolic syndrome. • Only autoimmune thyroiditis in subclinical hypothyroidism is associated with suicide attempts. • No significant difference between latent Hashimoto's thyroiditis and euthyroidism on all clinical characteristics. [ABSTRACT FROM AUTHOR]

Further understanding into the impacts of supercritical CO2 fluid exposure toward CO2 storage and coalbed methane (CH4) recovery is significant to evaluate validity, stability, and safety of CO2-ECBM. For purpose of addressing the potential impacts, the long-term static interactions between supercritical CO2 fluid and moisture-equilibrated coal matrices with various degrees of coalification were conducted at 318.15 K and 12.00 MPa for 240 days in this study. Furthermore, the changes of the physicochemical properties dominating adsorbability of moisture-equilibrated coals due to the exposure were revealed. Ultimately, the impacts of the exposure toward CH4 adsorbability of moisture-equilibrated coals were addressed. Results indicate that the long-term supercritical CO2 exposure induces complex effects typically including organic matter extraction, mineral dissolution and formation, and matrix swelling to the coals, thereby further reducing the micropores within pore diameter ranges of 0.38–0.71 nm and 0.74–0.90 nm of the low-rank moisture-equilibrated coals, and slightly increasing those of 0.40–0.70 nm and 0.75–0.90 nm of the high-rank moisture-equilibrated coal. Additionally, the complex effects reduce the mesopores with pore diameter less than 8.00 nm for all the coal samples. Moreover, the exposure alters the surface chemistry of the coals. Particularly, the exposure increases the oxygen-containing functional groups typically comprising C-O, C=O, and -COOH of the low-rank moisture-equilibrated coals by 25.32–27.16%, and weakens the graphitization of the high-rank coal by 34.00%. Moreover, the induced synergistic effects decrease the number of pores with diameter less than approximately 8.00 nm of all the moisture-equilibrated coals. Furthermore, the CO2 exposure significantly reduces CH4 adsorption capacity of the moisture-equilibrated coal matrices indicated by the decreasing amplitude in absolute adsorption amount of 6.20–18.00%. Overall, the long-term supercritical CO2 exposure could favor CH4 production during CO2-ECBM. Future study should focus on in-situ characterization and accurate quantitative analysis on extraction, mineral dissolution and formation, and matrix swelling due to CO2 exposure, and distinguishment in the contribution of these effects to pores and functional groups of coals. [ABSTRACT FROM AUTHOR]

To investigate the impact of multiple combustible gases produced by long-flame coal spontaneous combustion on the gas explosion limit and to guide the reoperation of the coal mine goaf and fire area, the influence of gas generated by coal spontaneous combustion on gas explosion limit is investigated in this paper using a temperature-programmed device and a 20 L spherical explosion device. The results show that the volume fraction of CO produced during the spontaneous combustion of coal samples is 0.47%, followed by CH4 and C2H6, and C2H4 has the lowest content. Simultaneously, the coal spontaneous combustion is divided by 30°C, 80°C, and 170°C as the threshold, depending on the different gas characteristics. Organic C2H4 and C2H6 produced by coal spontaneous combustion have a greater impact on the CH4 explosion limit than inorganic CO. The lower and upper limits of CH4 explosion were reduced to 2.98% and 12.2%, respectively, by 0.8% C2H6. C2H4 and C2H6 explosion limits change dramatically when mixed with CH4. The CO and CH4 mixture explosion limit decreases first and then increases. C2H4 and C2H6 have a significant impact on the explosion pressure of mixed gas and the lower explosion limit of gas. The lower explosion limit falls from 5.1% to 4.3% as the explosion pressure rises from 0.25 MPa to 0.29 MPa. [ABSTRACT FROM AUTHOR]

With the increasing demand for high-specific-strength materials for high-temperature applications, particularly in the aerospace field, novel (TiVCrZr)100−xWx (x = 5, 10, 15 and 20) refractory high-entropy alloys (RHEAs) were developed. The phase formation, microstructure, and mechanical properties were studied. The (TiVCrZr)100−xWx RHEAs exhibit a relatively high specific strength and low density compared with the W-containing RHEAs and most of the W-free RHEAs. In (TiVCrZr)100−xWx RHEAs, Laves, BCC and Ti-rich phases are formed, where the Laves phase is the major phase, and the volume fraction of the BCC phase increases with increasing W content. (TiVCrZr)100−xWx RHEAs exhibit dendrite structures, where W is enriched in the dendrite region, and increasing W-rich precipitations corresponding to the BCC phase are observed. The improvement of the strength and hardness of RHEAs is mainly attributed to the evolution of the microstructure and corresponding strengthening effect of W. The empirical parameters and calculated phase diagram were investigated, which further explain and verify the formation and variation of phases. The present findings give more insights into the formation of multi phases in (TiVCrZr)100−xWx RHEAs, and explore their application potential in the aerospace industry and nuclear reactors due to their high specific strength and low-activation constituent elements. [ABSTRACT FROM AUTHOR]

In this study, the adsorption experiments of water vapour on deep reservoir were conducted. The thermodynamics for water vapour adsorption were analysed. Results illustrate that primary binding centres have stronger affinity than secondary binding centres. Water molecule will be preferentially trapped at primary binding centres in low-pressure region. In high-pressure region, secondary adsorption predominates. Primary adsorption spontaneity increases with pressure. At secondary binding centres and total binding centres, the spontaneity degree quickly improves and then slowly decreases as pressure increases. The transfer of water molecules from the more energetic binding centres to the less binding centres leads to the initial reduction in entropy loss (ΔS) and isosteric heat of adsorption (Qst). The late enhancement in ΔS and Qst is caused by the growing water clusters. Water vapour adsorption can promote CH4 desorption. By occupying adsorption sites and reducing pore connectivity, water vapour adsorption causes an unfavourable effect on CO2 sequestration. [ABSTRACT FROM AUTHOR]

There are serious problems such as steam channeling and low oil-steam ratio when it comes to steam flooding. In order to improve its performance and to enhance oil recovery, foam agents and oil displacement agents are used to enhance the sweep efficiency and the displacement efficiency in steam flooding process. The design, development, and syntheses of high-performance low-cost foam agent and oil displacement agent were put forward in this paper. Evaluation experiment results showed excellent foaming performance and the high-temperature resistance of the foam agent. In addition, good interfacial performance and thermal stability of the oil displacement agent were also observed. The developed system was able to achieve ultra-low interfacial tension under steam flooding conditions. Laboratory experiments of chemical assisted steam flooding showed that the injection of the high-temperature foam agents and oil displacement agents totally enhanced oil recovery of 11.67%. Chemical assisted steam flooding field test has also been carried out in Gudao Zhongerbei Block of Shengli Oilfield. By June 2020, the cumulative oil production in the pilot area was 4.02 × 105 t with the reserve recovery percent of 54.6%, the enhanced oil production was 3.56 × 105 t and the enhanced oil recovery factor was 19.3%. [ABSTRACT FROM AUTHOR]

Integrated optimization of well placement and hydraulic fracture parameters in naturally fractured shale gas reservoirs is of significance to enhance unconventional hydrocarbon energy resources in the oil and gas industry. However, the optimization task usually presents intensive computation-cost due to numerous high-fidelity model simulations, particularly for field-scale application. We present an efficient multi-objective optimization framework supported by a novel hierarchical surrogate-assisted evolutionary algorithm and multi-fidelity modeling technology. In the proposed framework, both the net present value (NPV) and cumulative gas production (CGP) are regarded as the bi-objective functions that need to be optimized. The hierarchical surrogate-assisted evolutionary algorithm employs a novel multi-fidelity particle-swarm optimization of a global–local hybridization searching strategy where the low-fidelity surrogate model is capable of exploring the populations globally, while the high-fidelity models update the current populations and thus generate the next generations locally. The multi-layer perception is chosen as a surrogate model in this study. The performance of our proposed hierarchical surrogate-assisted global optimization approach is verified to optimize the well placement and hydraulic fracture parameters on a hydraulically fractured shale gas reservoir. The proposed surrogate model can obtain both the NPV and CPG with satisfactory accuracy with only 500 training samples. The surrogate model significantly contributes to the convergent performance of multi-objective optimization algorithm. [ABSTRACT FROM AUTHOR]

Given a set S of n points in the Euclidean plane, the two-center problem is to find two congruent disks of smallest radius whose union covers all points of S. Previously, Eppstein (SODA'97) gave a randomized algorithm of O (n log 2 n) expected time and Chan (CGTA'99) presented a deterministic algorithm of O (n log 2 n log 2 log n) time. In this paper, we propose an O (n log 2 n) time deterministic algorithm, which improves Chan's deterministic algorithm and matches the randomized bound of Eppstein. If S is in convex position, then we solve the problem in O (n log n log log n) deterministic time. Our results rely on new techniques for dynamically maintaining circular hulls under point insertions and deletions, which are of independent interest. [ABSTRACT FROM AUTHOR]

Text classification is a popular research topic in the natural language processing. Recently solving text classification problems with graph neural network (GNN) has received increasing attention. However, current graph-based studies ignore the hidden information in text syntax and sequence structure, and it is difficult to use the model directly for processing new documents because the text graph is built based on the whole corpus including the test set. To address the above problems, we propose a text classification model based on long short-term memory network (LSTM) and graph attention network (GAT). The model builds a separate graph based on the syntactic structure of each document, generates word embeddings with contextual information using LSTM, then learns the inductive representation of words by GAT, and finally fuses all the nodes in the graph together into the document embedding. Experimental results on four datasets show that our model outperforms existing text classification methods with faster convergence and less memory consumption than other graph-based methods. In addition, our model shows a more notable improvement when using less training data. Our model proves the importance of text syntax and sequence information for classification results. [ABSTRACT FROM AUTHOR]

The remaining useful life (RUL) prediction is important for improving the safety, supportability, maintainability, and reliability of modern industrial equipment. The traditional data-driven rolling bearing RUL prediction methods require a substantial amount of prior knowledge to extract degraded features. A large number of recurrent neural networks (RNNs) have been applied to RUL, but their shortcomings of long-term dependence and inability to remember long-term historical information can result in low RUL prediction accuracy. To address this limitation, this paper proposes an RUL prediction method based on adaptive shrinkage processing and a temporal convolutional network (TCN). In the proposed method, instead of performing the feature extraction to preprocess the original data, the multi-channel data are directly used as an input of a prediction network. In addition, an adaptive shrinkage processing sub-network is designed to allocate the parameters of the soft-thresholding function adaptively to reduce noise-related information amount while retaining useful features. Therefore, compared with the existing RUL prediction methods, the proposed method can more accurately describe RUL based on the original historical data. Through experiments on a PHM2012 rolling bearing data set, a XJTU-SY data set and comparison with different methods, the predicted mean absolute error (MAE) is reduced by 52% at most, and the root mean square error (RMSE) is reduced by 64% at most. The experimental results show that the proposed adaptive shrinkage processing method, combined with the TCN model, can predict the RUL accurately and has a high application value. [ABSTRACT FROM AUTHOR]

The received signal of passive radar based on mobile communication signals contains direct and multipath interference (DMI) signals from multiple co-channel base stations (CCBS). The direct signal spatial spectrum of each CCBS should be obtained first to eliminate the co-channel interference. The performance of the traditional spatial spectrum estimation algorithms based on uniform linear array (ULA) is related to the number of array elements. In the complex co-channel interference environment, the array requires an ultra-large number of array elements and the spatial spectrum estimation resolution is poor. This paper proposes a method for estimating the direct signal spatial spectrum of the CCBS by fusing coprime array and compressive sensing. Firstly, an augmented virtual array signal is constructed by using the second-order statistics of the received signals of the coprime array and then the compressive sensing algorithm is used to estimate the spatial spectrum of the direct signal of the CCBS. The proposed method can achieve higher resolution and higher-degrees-of-freedom (DOFs) performance than traditional ULA by using the same number of array elements. The effectiveness of the proposed method is verified by numerical simulation analysis and experimental data. [ABSTRACT FROM AUTHOR]

Massive hydraulic fracturing (MHF) is currently the most effective technology used to create fracture networks with sufficient conductivity and maximize the stimulated reservoir volume (SRV) in tight oil and gas reservoirs. The newly initiated fracture networks during MHF usually exhibit complex fracture morphology and contain intersected fractures and fracture branches. The conductivity of these fractures plays a pivotal role in determining long-term productivity. Due to the complex geometry, it is difficult to accurately evaluate intersected fracture conductivity through traditional conductivity measurement methods and devices which are designed for a single primary fracture. Unlike previous studies where fracture conductivity was measured using two rock slabs under single-direction (vertical) loading, we establish a novel conductivity measurement apparatus that can mimic different fracture intersection scenarios under both vertical and transverse loading to facilitate the evaluation of intersected fracture conductivity. Based on this apparatus, a standard conductivity measurement framework for intersected fractures under biaxial compaction conditions is also proposed, and stable and reliable conductivity testing data are obtained. Sensitivity analyses are performed to find out the controlling factors of intersected fracture conductivity and the corresponding conductivity evolution law. Results indicate that the overall intersected fracture conductivity of intersected fractures can be divided into three stages, with closure pressure increasing, videlicet, the conductivity rapid reduction stage at low closure pressure, the conductivity slow reduction stage, and the conductivity stabilization stage. Higher proppant concentration results in higher conductivity. However, the conductivity differences among cases with different proppant concentration are relatively small at high closure pressure (conductivity stabilization stage). The more complex the fracture intersecting pattern is, the higher the conductivity would be. The experimental results can provide guidance for the design of proppant placement procedure for intersected fractures. [ABSTRACT FROM AUTHOR]

The heat extraction performance of the enhanced geothermal system is simulated by using COMSOL software. The effects of six factors, such as the thermal conductivity of heat reservoir, matrix permeability, fracture width, injection temperature, injection flow rate, and the number of wells, on the heat extraction performance of EGS heat reservoir for 40 years are analyzed. The results show that the matrix permeability and injection flow are the main factors affecting the heat production performance of the EGS geothermal reservoir, while the thermal conductivity, fracture width, and injection temperature have little effect on the heat production performance of the EGS geothermal reservoir. Although increasing the number of production wells can improve the uneven distribution of the flow field to improve the system heat performance, taking into account the existing drilling technology and cost, the cost is higher, and the two-well system is still the basic form of absorbing rock heat. [ABSTRACT FROM AUTHOR]

Synthetic aperture radar (SAR) image ship detection is currently a research hotspot in the field of national defense science and technology. However, SAR images contain a large amount of coherent speckle noise, which poses significant challenges in the task of ship detection. To address this issue, we propose filter convolution, a novel design that replaces the traditional convolution layer and suppresses coherent speckle noise while extracting features. Specifically, the convolution kernel of the filter convolution comes from the input and is generated by two modules: the kernel-generation module and local weight generation module. The kernel-generation module is a dynamic structure that generates dynamic convolution kernels using input image or feature information. The local weight generation module is based on the statistical characteristics of the input images or features and is used to generate local weights. The introduction of local weights allows the extracted features to contain more local characteristic information, which is conducive to ship detection in SAR images. In addition, we proved that the fusion of the proposed kernel-generation module and the local weight module can suppress coherent speckle noise in the SAR image. The experimental results show the excellent performance of our method on a large-scale SAR ship detection dataset-v1.0 (LS-SSDD-v1.0). It also achieved state-of-the-art performance on a high-resolution SAR image dataset (HRSID), which confirmed its applicability. [ABSTRACT FROM AUTHOR]

The unconventional reservoirs such as carbonate formation develops complex and diverse storage space structures, and it is composed of large-scale cavity, dissolved vug, and fractures. The carbonate reservoir is highly heterogeneous. Acid fracturing of carbonate reservoir is completed through the complex mechanical mechanism of interaction between vug and hydraulic fracture (HF). We use the equivalent method of reducing the rock strength by acid etching and serious fluid leakoff during interaction of HF and vug to establish a finite element (FE) model of HF propagation during acid fracturing in the fractured-vuggy carbonate reservoir. The model considers the effect of serious fluid leakoff during interaction between HF and vug, mechanism of interaction between HFs and the fracture-vug system, and change in acid etching intensity. Then, we carry out numerical simulation on impacts of injection rate, fluid viscosity, leakoff behavior in fractures and vugs, and natural fracture (NF) approaching angle on HF propagation in acid fracturing and compare the characteristics of injection pressure, fracture pressure, and HF size. It is suggested that the acid fracturing treatment should be operated by increasing the acid solution viscosity to reduce fluid leakoff, injecting fracturing fluid and acid fluid alternatively, increasing injection rate, and injecting fibers and ceramics when small pressure drop occurs during the HF interacts with the fracture-vug. When a large pressure drop occurs, it is suggested that the middle-low viscosity acid be injected at a low rate to etch the carbonate rock and enhance the fracture conductivity. HF propagates under higher pressure when the NF approaching angle is smaller. [ABSTRACT FROM AUTHOR]

In this paper, the relationship between additive particle size and properties of AgSnO2 contact materials was studied. La2O3 and Bi2O3 were selected as additives for contact materials. AgSnO2 contact materials were successfully prepared by powder metallurgy, the wettability and electrical contact properties of AgSnO2 contact materials with five particle sizes of additives were investigated. The results show that the wettability and electrical contact properties of the two contact materials are better when the particle size of additives is 500 nm and 1000 nm respectively. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Cu 2 O NP@CuHHTP heterojunction nanoarrays were obtained by partly decomposing the conductive MOF CuHHTP with simple and mild electrochemical reduction. They display super sensing performance for H 2 O 2. [Display omitted] Transition metal oxide/metal–organic framework heterojunctions (TMO@MOF) that combine the large specific surface area of MOFs with TMOs' high catalytic activity and multifunctionality, show excellent performances in various catalytic reactions. Nevertheless, the present preparation approaches of TMO@MOF heterojunctions are too complex to control, stimulating interests in developing simple and highly controllable methods for preparing such heterojunction. In this study, we propose an in situ electrochemical reduction approach to fabricating Cu 2 O nanoparticle (NP)@CuHHTP heterojunction nanoarrays with a graphene-like conductive MOF CuHHTP (HHTP is 2,3,6,7,10,11-hexahydroxytriphenylene). We have discovered that size-controlled Cu 2 O nanoparticles could be in situ grown on CuHHTP by applying different electrochemical reduction potentials. Also, the obtained Cu 2 O NP@CuHHTP heterojunction nanoarrays show high H 2 O 2 sensitivity of 8150.6 μA·mM−1·cm2 and satisfactory detection performances in application of measuring H 2 O 2 concentrations in urine and serum samples. This study offers promising guidance for the synthesis of MOF-based heterojunctions for early cancer diagnosis. [ABSTRACT FROM AUTHOR]